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            <div><h3 class="title">
                <a name="asio.reference.DynamicBuffer_v2"></a><a class="link" href="DynamicBuffer_v2.html"
                                                                 title="Dynamic buffer requirements (version 2)">Dynamic
                buffer requirements
                (version 2)</a>
            </h3></div>
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    <p>
        A dynamic buffer encapsulates memory storage that may be automatically resized
        as required.
    </p>
    <p>
        A dynamic buffer type <code class="computeroutput"><span class="identifier">X</span></code> shall
        satisfy the requirements of <code class="computeroutput"><span
            class="identifier">CopyConstructible</span></code>
        (C++ Std, [copyconstructible]) types in addition to those listed below.
    </p>
    <p>
        In the table below, <code class="computeroutput"><span class="identifier">X</span></code> denotes
        a dynamic buffer class, <code class="computeroutput"><span class="identifier">x</span></code>
        denotes a value of type <code class="computeroutput"><span class="identifier">X</span><span class="special">&amp;</span></code>,
        <code class="computeroutput"><span class="identifier">x1</span></code>
        denotes values of type <code class="computeroutput"><span class="keyword">const</span> <span class="identifier">X</span><span
            class="special">&amp;</span></code>,
        <code class="computeroutput"><span class="identifier">pos</span></code> and <code class="computeroutput"><span
            class="identifier">n</span></code>
        denote values of type <code class="computeroutput"><span class="identifier">size_t</span></code>,
        and <code class="computeroutput"><span class="identifier">u</span></code> denotes an identifier.
    </p>
    <div class="table">
        <a name="asio.reference.DynamicBuffer_v2.t0"></a>
        <p class="title"><b>Table 13. DynamicBuffer_v2 requirements</b></p>
        <div class="table-contents">
            <table class="table" summary="DynamicBuffer_v2 requirements">
                <colgroup>
                    <col>
                    <col>
                    <col>
                </colgroup>
                <thead>
                <tr>
                    <th>
                        <p>
                            expression
                        </p>
                    </th>
                    <th>
                        <p>
                            type
                        </p>
                    </th>
                    <th>
                        <p>
                            assertion/note<br> pre/post-conditions
                        </p>
                    </th>
                </tr>
                </thead>
                <tbody>
                <tr>
                    <td>
                        <p>
                            <code class="computeroutput"><span class="identifier">X</span><span
                                    class="special">::</span><span class="identifier">const_buffers_type</span></code>
                        </p>
                    </td>
                    <td>
                        <p>
                            type meeting <a class="link" href="ConstBufferSequence.html"
                                            title="Constant buffer sequence requirements">ConstBufferSequence</a>
                            requirements.
                        </p>
                    </td>
                    <td>
                        <p>
                            This type represents the underlying memory as a sequence of @c
                            const_buffer objects.
                        </p>
                    </td>
                </tr>
                <tr>
                    <td>
                        <p>
                            <code class="computeroutput"><span class="identifier">X</span><span
                                    class="special">::</span><span class="identifier">mutable_buffers_type</span></code>
                        </p>
                    </td>
                    <td>
                        <p>
                            type meeting <a class="link" href="MutableBufferSequence.html"
                                            title="Mutable buffer sequence requirements">MutableBufferSequence</a>
                            requirements.
                        </p>
                    </td>
                    <td>
                        <p>
                            This type represents the underlying memory as a sequence of @c
                            mutable_buffer objects.
                        </p>
                    </td>
                </tr>
                <tr>
                    <td>
                        <p>
                            <code class="computeroutput"><span class="identifier">x1</span><span
                                    class="special">.</span><span class="identifier">size</span><span
                                    class="special">()</span></code>
                        </p>
                    </td>
                    <td>
                        <p>
                            <code class="computeroutput"><span class="identifier">size_t</span></code>
                        </p>
                    </td>
                    <td>
                        <p>
                            Returns the size, in bytes, of the underlying memory.
                        </p>
                    </td>
                </tr>
                <tr>
                    <td>
                        <p>
                            <code class="computeroutput"><span class="identifier">x1</span><span
                                    class="special">.</span><span class="identifier">max_size</span><span
                                    class="special">()</span></code>
                        </p>
                    </td>
                    <td>
                        <p>
                            <code class="computeroutput"><span class="identifier">size_t</span></code>
                        </p>
                    </td>
                    <td>
                        <p>
                            Returns the permitted maximum size of the underlying memory.
                        </p>
                    </td>
                </tr>
                <tr>
                    <td>
                        <p>
                            <code class="computeroutput"><span class="identifier">x1</span><span
                                    class="special">.</span><span class="identifier">capacity</span><span
                                    class="special">()</span></code>
                        </p>
                    </td>
                    <td>
                        <p>
                            <code class="computeroutput"><span class="identifier">size_t</span></code>
                        </p>
                    </td>
                    <td>
                        <p>
                            Returns the maximum size to which the underlying memory can grow
                            without requiring reallocation.
                        </p>
                    </td>
                </tr>
                <tr>
                    <td>
                        <p>
                            <code class="computeroutput"><span class="identifier">x1</span><span
                                    class="special">.</span><span class="identifier">data</span><span
                                    class="special">(</span><span class="identifier">pos</span><span
                                    class="special">,</span>
                                <span class="identifier">n</span><span class="special">)</span></code>
                        </p>
                    </td>
                    <td>
                        <p>
                            <code class="computeroutput"><span class="identifier">X</span><span
                                    class="special">::</span><span class="identifier">const_buffers_type</span></code>
                        </p>
                    </td>
                    <td>
                        <p>
                            Returns a constant buffer sequence <code class="computeroutput"><span
                                class="identifier">u</span></code>
                            that represents the underlying memory beginning at offset <code class="computeroutput"><span
                                class="identifier">pos</span></code>, and where <code class="computeroutput"><span
                                class="identifier">buffer_size</span><span class="special">(</span><span
                                class="identifier">u</span><span class="special">)</span>
                            <span class="special">&lt;=</span> <span class="identifier">n</span></code>.
                        </p>
                    </td>
                </tr>
                <tr>
                    <td>
                        <p>
                            <code class="computeroutput"><span class="identifier">x</span><span class="special">.</span><span
                                    class="identifier">data</span><span class="special">(</span><span
                                    class="identifier">pos</span><span class="special">,</span>
                                <span class="identifier">n</span><span class="special">)</span></code>
                        </p>
                    </td>
                    <td>
                        <p>
                            <code class="computeroutput"><span class="identifier">X</span><span
                                    class="special">::</span><span class="identifier">mutable_buffers_type</span></code>
                        </p>
                    </td>
                    <td>
                        <p>
                            Returns a mutable buffer sequence <code class="computeroutput"><span
                                class="identifier">u</span></code>
                            that represents the underlying memory beginning at offset <code class="computeroutput"><span
                                class="identifier">pos</span></code>, and where <code class="computeroutput"><span
                                class="identifier">buffer_size</span><span class="special">(</span><span
                                class="identifier">u</span><span class="special">)</span>
                            <span class="special">&lt;=</span> <span class="identifier">n</span></code>.
                        </p>
                    </td>
                </tr>
                <tr>
                    <td>
                        <p>
                            <code class="computeroutput"><span class="identifier">x</span><span class="special">.</span><span
                                    class="identifier">grow</span><span class="special">(</span><span
                                    class="identifier">n</span><span class="special">)</span></code>
                        </p>
                    </td>
                    <td>
                    </td>
                    <td>
                        <p>
                            Requires: <code class="computeroutput"><span class="identifier">size</span><span
                                class="special">()</span> <span class="special">+</span> <span
                                class="identifier">n</span> <span class="special">&lt;=</span>
                            <span class="identifier">max_size</span><span class="special">()</span></code>.<br>
                            <br> Extends the underlying memory to accommodate <code class="computeroutput"><span
                                class="identifier">n</span></code> additional bytes at the end.
                            The dynamic buffer reallocates memory as required. All constant
                            or mutable buffer sequences previously obtained using <code class="computeroutput"><span
                                class="identifier">data</span><span class="special">()</span></code>
                            are invalidated.<br> <br> Throws: <code class="computeroutput"><span class="identifier">length_error</span></code>
                            if <code class="computeroutput"><span class="identifier">size</span><span
                                class="special">()</span>
                            <span class="special">+</span> <span class="identifier">n</span>
                            <span class="special">&gt;</span> <span class="identifier">max_size</span><span
                                    class="special">()</span></code>.
                        </p>
                    </td>
                </tr>
                <tr>
                    <td>
                        <p>
                            <code class="computeroutput"><span class="identifier">x</span><span class="special">.</span><span
                                    class="identifier">shrink</span><span class="special">(</span><span
                                    class="identifier">n</span><span class="special">)</span></code>
                        </p>
                    </td>
                    <td>
                    </td>
                    <td>
                        <p>
                            Removes <code class="computeroutput"><span class="identifier">n</span></code> bytes
                            from the end of the underlying memory. If <code class="computeroutput"><span
                                class="identifier">n</span></code>
                            is greater than the size of the underlying memory, the entire underlying
                            memory is emptied. All constant or mutable buffer sequences previously
                            obtained using <code class="computeroutput"><span class="identifier">data</span><span
                                class="special">()</span></code> are invalidated.
                        </p>
                    </td>
                </tr>
                <tr>
                    <td>
                        <p>
                            <code class="computeroutput"><span class="identifier">x</span><span class="special">.</span><span
                                    class="identifier">consume</span><span class="special">(</span><span
                                    class="identifier">n</span><span class="special">)</span></code>
                        </p>
                    </td>
                    <td>
                    </td>
                    <td>
                        <p>
                            Removes <code class="computeroutput"><span class="identifier">n</span></code> bytes
                            from the beginning of the underlying memory. If <code class="computeroutput"><span
                                class="identifier">n</span></code>
                            is greater than the size of the underlying memory, the entire underlying
                            memory is emptied. All constant or mutable buffer sequences previously
                            obtained using <code class="computeroutput"><span class="identifier">data</span><span
                                class="special">()</span></code> are invalidated.
                        </p>
                    </td>
                </tr>
                </tbody>
            </table>
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            <div class="copyright-footer">Copyright © 2003-2022 Christopher M. Kohlhoff<p>
                Distributed under the Boost Software License, Version 1.0. (See accompanying
                file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
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